80 adult patients (40 women, 40 men) scheduled to undergo elective surgical procedures requiring general anesthesia and necessitating endotracheal intubation, were included in this study. Patients eligible for participation were aged 18-60 yrs., ASA physical status I or II and BMI < 30 kg/m2. Before anesthesia induction, CP was verified as follow: the cricoid cartilage was first identified and then held between the thumb and middle finger and the pressure was applied by the index finger with a force that could be tolerated by the patient. After loss of consciousness, four predetermined forces: 0 , 10 , 20 and 30 N were chosen in a randomized method. Therefore, after applying the predetermined force, a GT 20 F insertion trial was performed and two outcomes were considered: 1) Failure of GT insertion: effective CP. The next trials were not attempted. 2) Success of GT insertion: ineffective CP. The patient received a second attempt with increasing force to the next scale of force. If the attempt was effective (failure of GT insertion) , the relevant force is considered as the effective CP force. Same trial was repeated using 0, 10, 20 and 30 N respectively in in a randomized fashion for each patient. The cricoid force was standardized by reproducing 10, 20 and 30 N on a weighing scale prior to each application.